Gas turbines are widely used in industrial and power generation operations. A gas turbine generally includes, in serial flow order, a compressor, a combustion section and a turbine. The combustion section may include multiple combustors annularly arranged around an outer casing. In operation, a working fluid such as ambient air is progressively compressed as it flows through the compressor. A portion of the compressed working fluid is routed from the compressor to each of the combustors where it is mixed with a fuel and burned in a combustion chamber or zone to produce combustion gases. The combustion gases are routed through the turbine along a hot gas path where thermal and/or kinetic energy is extracted from the combustion gases via turbine rotors blades coupled to a rotor shaft, thus causing the rotor shaft to rotate and produce work and/or thrust.
Particular combustion systems utilize bundled tube type fuel nozzles for premixing a gaseous fuel with the compressed air upstream from the combustion zone. An aft plate of the bundled tube fuel nozzle is disposed at a downstream end of the bundled tube fuel nozzle. A “hot side” of the aft plate is positioned proximate to outlets of each tube of the bundle tube fuel nozzle. As such, the hot side of the aft plate is exposed to extreme heat from the combustion gases.